The present invention is directed to a dental x-ray diagnostics installation for producing overview pictures or panoramic exposures of slices of the skull of the patient, particularly in the region of the jaw. The installation includes an x-ray tube pivotable around an axis and displaceable in a plane proceeding perpendicular to the axis, a film holder lying opposite the exposure unit and movable relative thereto, a head holding arrangement for holding the head on the axis between the two units and a control arrangement or means which first controls the pivoting and displacement motion of the exposure unit relative to the head holder and secondly controls the movement of the film holder relative to the x-ray tube, so that different slices of the skull can be exposed and the path of the respective slices to be exposed is selectable on the basis of input means.
U.S. Pat. No. 4,418,419 which claims priority from German Application No. 30 07 935 and which disclosure is incorporated by reference thereto, discloses an x-ray dental diagnostic installation or dental tomographic apparatus wherein an x-ray unit and film holder pivot around a first axis and are displaceable in a plane perpendicular to said first axis to take dental panoramic radiographs. In the known x-ray diagnostic installation, the input means comprises a member introducable into the mouth of the patient, which is provided with a plurality of pressure contacts which are activated by biting of the input means by the patient. The switch condition of the pressure contacts produces signals for a control means which allows the movement of the exposure unit and the film holder to be controlled during the exposure so that a slice or path proceeding through the actual pressure contacts in the region of the jaw of the patient is exposed. Under the precondition that the patient has normal tooth alignment, the known x-ray diagnostics installation will allow high quality panoramic radiographs of slices that proceed in the region of the jaw of the patient to be produced. However, when the patient has even a slight malalignment of the teeth, a faultless exposure quality in the region of the dental roots is no longer guaranteed with certainty. When serious malalignments of the teeth are present, there is a risk that the individual teeth of the patient will not be sharply imaged due to the fact that only relatively few pressure contacts are present. Moreover, the overview exposure of, for example, temporomandibular slice or the slices proceeding in the region of the maxillary sinus cannot be produced with the known x-ray diagnostic installation because the path of the slice is dependent on the shape of the teeth of the patient due to the fashioning of the input means as mentioned hereinabove.